Significant road closures are planned along downtown Baltimore streets beginning at 9 p.m. Monday as the streets are converted into a 2-mile race course to accommodate the Grand Prix.

The race, now in its third year, runs from Friday to Sunday, but road closures are necessary to set up and tear down the track, according to the city Department of Transportation

By Thursday, all roadways along the race course will be closed to traffic. Traffic patters won't return to normal until 6 a.m. Tuesday.

Expect significant delays when entering the city, especially from the south. Motorists are encouraged to use alternate routes and allow additional travel time.

While businesses will be open along the route and throughout the city, strict parking restrictions will be in place. Residential permit parking regulations will also be enforced.

If a vehicle is towed, the driver should call 311 for information.

The use of public transportation, including the Light Rail, metro and Charm City Circulator, is encouraged.

By 9 p.m. Monday, the following roads will be closed: Sharp Street between Pratt and Conway Streets, Hopkins Place between Pratt and Lombard Streets, Hanover Street between Pratt and Lombard Streets, and Lee Street between Light and Charles Streets.

By 11 p.m. Monday, Maryland Stadium Authority Service Drive between Russell Street and the light rail crossing will close and will not reopen at 6 a.m. Tuesday.

Pratt Street will be closed to traffic during the event, but two-way local access will be open from Lombard Street to the road closure near Pratt Street throughout the event.

Light Street will also be closed during the event, but two-way traffic will be open for local access from Charles Street eastward to the closure near Light Street.

Public transportation routes also will be modified, according to the DOT. Normal service will resume on at 6 a.m. Tuesday.

Local MTA buses numbers 3 and 3X will be diverted beginning at 9 p.m. Monday.

The Light Rail will suspend service between the Baltimore Street and Hamburg Street stops from 3 a.m. Thursday until 5 a.m. Tuesday.. Free shuttle buses will operate between the Baltimore Street and Hamburg Street stops.

A revised schedule will be in place for the Charm City Circulator's Orange, Purple and Banner routes beginning at 6:30 a.m. Thursday. A normal schedule will return at 9 p.m. Monday.

The metro service will not be affected by the race.

Walking and biking paths will also be affected, beginning at 9 p.m. Wednesday. Pedestrians and cyclists can use the Inner Harbor Promenade to bypass the track area to the east, and the west sidewalk of Greene Street to avoid the track on the west side of the circuit.

For more traffic information and a map of the closures, go to http://www.gptraffic.com.

Check the MTA website at http://www.mta.maryland.gov for schedule changes. Route revisions for the Charm City Circulator are available at http://www.charmcitycirculator.com.